Monodeuterated derivatives of;the salts of tyrosine, valine, glycylglycine,
and glycylglycylglycine are investigated by infrared spectroscopy. Irradia
tion in the spectral region of the N-D stretch bands produces spectral hole
s and antiholes. These result from rotation of N-D-containing moieties. The
holes and antiholes identify the vibrations of the amino group and provide
information on the hydrogen-bonding environment. Both the various amino ac
id salts and the two peptide salts hole burn, suggesting that infrared hole
burning will provide a useful tool for investigating a range of biological
ly interesting materials.